"I had someone correct my grammar on a blind date once, and I knew within the first 10 minutes that the date was over," the Walk the Line Oscar winner, 34, said at a press gathering for her new movie, James L. Brooks's How Do You Know, opening Dec. 17.

Even worse, "I don't even remember what I said – I probably said 'ain't.' " But the lesson she wishes to pass on: "Just don't correct my grammar. I'm from Tennessee. I probably say everything wrong."